Recent activity

The geomagnetic field was quiet to unsettled on August 28. Solar
wind
speed ranged between 358 and 446 (all day average 395) km/sec.

Solar flux measured at 20h UTC on 2.8 GHz was 89.8. The planetary
A
index was 7 (STAR Ap - based on the mean of three hour interval ap
indices: 6.6).
Three hour interval K indices: 22011123 (planetary), 13122113 (Boulder).

The background x-ray flux is at the class A8 level.

At midnight there were 5 spotted regions on the visible solar disk.
The solar flare activity level was moderate. A total of 1 M class event was recorded during the day.

Region 10800 decayed further and lost the leader spots.
Region 10801 decayed and was quiet.
Region 10803 decayed and lost nearly half of its penumbral area. Flare: M1.6 at
10:28 UTC.
Region 10804 reemerged with a single spot.
Region 10805 was generally unchanged with all spots within a single penumbra.

Coronal mass ejections (CMEs)

August 26-28: No obvious partly or fully Earth directed CMEs were
observed.

Coronal holes

A recurrent coronal hole (CH184) in the southern hemisphere was likely in an Earth facing position on August 27-28.

Processed SOHO/EIT 284 image at 01:06 UTC on August 29. The
darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet
to active on August 29. A high speed stream from CH184 could reach Earth on August 30 and cause unsettled to
minor storm conditions that day and on August 31.

Coronal holes (1)

Coronal mass ejections (2)

M and X class flares (3)

1) Effects from a coronal hole could reach Earth
within the next 5 days. When the high speed stream has arrived
the color changes to green.
2) Material from a CME is likely to impact Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next
48 hours.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation
along
east-west paths over high and upper middle latitudes is very poor.
Propagation on long distance northeast-southwest paths is poor to very poor. Trans
Atlantic propagation conditions are normally monitored every night on
1470 kHz. Dominant station tonight: Radio Cristal del Uruguay with an unusually weak signal. There weren't many other stations
with audio during the night, only a few from Brazil (740, 930, 1130 kHz) and Argentina (950, 1070, 1510 kHz).

Data for all numbered solar regions according to the Solar Region
Summary provided by
NOAA/SEC. Comments are my own, as is the
STAR spot count (spots observed at or inside a few hours before
midnight) and data for regions not numbered by SEC or where SEC has
observed no spots.
SEC active region numbers in the table below and in the active region
map above are the historic
SEC/USAF numbers.

Active region

Date numbered

SEC
spot
count

STAR
spot
count

Location at midnight

Area

Classification

Comment

10800

2005.08.19

4

2

N16W74

0030

BXO

classification was HSX at midnight, location: N19W72

10801

2005.08.20

4

1

N09W44

0040

CSO

classification was HSX at midnight, area 0020, location: N10W47

10802

2005.08.24

S12W39

plage

10803

2005.08.24

37

12

N11E27

0100

DSI

beta-gamma area was 0060 at midnight

10804

2005.08.25

1

1

N11W27

0000

AXX

10805

2005.08.27

3

3

S08E60

0100

DSO

classification was HAX at midnight, area 0060
location: S09E59

Total spot count:

49

19

SSN:

99

69

Monthly solar cycle data

Month

Average solar
flux at Earth

International sunspot number

Smoothed sunspot number

2000.04

184.2

125.5

120.8
cycle 23 sunspot max.

2000.07

202.3

170.1

119.8

2001.12

235.1

132.2

114.6 (-0.9)

2004.06

97.4

43.2

41.6 (-2.2)

2004.07

119.1

51.1

40.2 (-1.4)

2004.08

109.6

40.9

39.2 (-1.0)

2004.09

103.1

27.7

37.5 (-1.7)

2004.10

105.9

48.0

35.9 (-1.6)

2004.11

113.2

43.5

35.3 (-0.6)

2004.12

94.5

17.9

35.2 (-0.1)

2005.01

102.2

31.3

34.6 (-0.6)

2005.02

97.2

29.2

(33.5 predicted, -1.1)

2005.03

89.9

24.5

(32.1 predicted, -1.4)

2005.04

86.0

24.4

(30.2 predicted, -1.9)

2005.05

99.3

42.6

(27.6 predicted, -2.6)

2005.06

93.7

39.6

(26.1 predicted, -1.5)

2005.07

96.4

39.9

(25.1 predicted, -1.0)

2005.08

91.0 (1)

59.0 (2)

(23.2 predicted, -1.9)

1) Running average based on the daily 20:00 UTC observed solar flux
value at 2800 MHz.
2) Unofficial, accumulated value based on the Boulder (NOAA/SEC)
sunspot number. The official international sunspot number is typically
30-50% lower.

This report has been prepared by Jan
Alvestad. It is based partly on my own observations and analysis,
and
partly on data from some of these solar data sources.
All time references are to the UTC day. Comments and suggestions are
always welcome.